Automatic developing machines, which develop, fix and bleach photographic light-sensitive materials, require that their respective processing baths be supplied with fixed amounts of processing agents in the form of replenishing solutions, because of the loss resulting from taking out by processed light-sensitive materials as well as evaporation, oxidation or degradation.
These replenishing processing agents are generally supplied in the form of solid or highly concentrated solution, and dissolved or diluted before use.
The present inventors disclosed, in Japanese Patent O.P.I. Publication No. 135887/1990, an automatic developing machine and related solid processing agents which are supplied as large blocks, dissolved in replenishing solution tanks and pumped into processing tanks.
As stated above, the product form of conventional photographic processing agents falls into two large types; namely, liquid and powder. And automatic developing machines,used for processing large amounts of light-sensitive materials, require that the processing tanks be replenished with respective replenishing solutions to replenish processing solutions consumed in proportion to the processed amount.
In feeding a replenishing solution to a processing bath, while a liquid type processing agent can be simply pumped from replenishing tank to processing tank, a powder type processing agent is directly fed into a processing tank and stirred for a certain time, or dissolved in a warm water beforehand and poured into a processing tank.
The powder type photographic processing agent, which used to be widely utilized, was gradually replaced by the liquid type. The reason lies firstly in the inconvenience that it needs a dissolving procedure, such as heating or stirring of a solution containing the agent, which is not suited for continuous operation of the automatic developing machines; and secondly in the necessity for complicated manufacturing contrivances in order to maintain components of a processing agent at a uniform mixing ratio.
However, the powder type processing agent is still used and improved in many ways at present, since it has a decisive advantage over the liquid type in transport and supply because of its lightness and non-bulkiness.
For example, there is utilized a vacuum-packed solid processing agent, in which a powder processing agent is divided by components formed in layers, then packed in an airtight bag. In this case, a contrivance is made to separate components in the bag which react one another upon contact. But this package allows the processing agent to be crushed to powder upon unpacking; therefore, it is not suited to the automatic solution preparing unit for a replenishing processing solution built in the automatic developing machine, and when handled manually, it shows a disadvantage of scattering fine powder.